Multicontact switch



Aug? 1970 G. K. DATCHENKO ETAL 3,523,165

MULTICONTACT SWITCH Filed Jan. 15, 1968 United States Patent 3,523,165 MULTICONTACT SWITCH Gennady Kuzmich Datchenko, Ulitsa Ofitserskaya 48a, kv. 69, and Boris Vasilievich Lyalin, Ulitsa Krasnaya 34, kv. 8, both of Krasnodar, U.S.S.R.

Filed Jan. 15, 1968, Ser. No. 697,722 Int. Cl. H01h N22 US. Cl. 200-11 6 Claims ABSTRACT OF THE DISCLOSURE A multicontact switch in which current carrying brushes are mounted on a displaceable yoke by two crossing axles one of which is oriented in the direction of displacement of the yoke and is pivotably connected to a clamp which is slidable in the yoke while the other axle pivotably supports the brushes. The brushes face contacts on a fixed base and the axles lie in a common plane substantially disposed at the level of the opposed surfaces of the brushes and contacts.

The present invention relates to switching devices, and more particularly to multicontact switches.

Known devices, for example, rotary switches contain make-and-break contact sets arranged in concentric circles on an insulation base around an axle on which a rotary yoke is attached. This yoke carries laminated brushes with their loose ends locked in turning joints which insure limited swings of the brushes in one plane.

The brush pressure on the contact surface is distributed irregularly in such switches and may cause misalignments and brush jamming, which result in intense and uneven wear of switch contacts. The latter fact impairs the accuracy and stability of the measuring instrument in which the switch is utilized.

It is an object of the present invention to provide a dependable multicontact switch featuring a long service life.

It is another object of the invention to provide a switch insuring a stable contact state of electrical circuits with a minimum of variations.

These and otherobjects are accomplished by providing a multicontact switch, wherein self-positioning of the current-carrying brushes on the contact'surface is insured for attaining uniform contact pressure.

To this end, in the switch of the present invention the brushes are attached to the yoke so that they are free to rotate about crossing axles disposed at the level of the contact surface in a plane coinciding or nearly coinciding with that of the opposed faces of the brushes and the contacts.

According to a preferred embodiment of the invention the brushes are mounted on perpendicular pivotally connected axles associated with a common clamp which is mounted loosely in the yoke and is urged towards the contacts to insure pressing of the brush faces against the contact surfaces.

The invention will become more apparent upon consideration of an exemplary embodiment thereof taken in conjunction with the accompanying drawing in which the multicontact switch according to the invention is shown in side elevation and partly in section.

Mounted on an insulation base 1 are make-andbreak contacts 2 arranged in pairs along concentric circles around the axis of a central pin 3.

A rotary yoke 4 is mounted on shaft 3 and is provided with a hole 5 in which a clamp 6 carrying laminated ice current-carrying brushes 7 in pairs, is mounted freely. The brushes 7 are attached, by means of angle members 8, to an axle 9 so as to be free to rotate about this axle. Axle 9, in its turn, is coupled in the middle thereof via an articulated joint with the end of clamp =6 so as to be free to rotate about an axle 10.

Axles 9 and 10 are perpendicular to each other and disposed at the level of the contact surface in a plane which is adjacent to or coincident with that of the opposed working faces of brushes 7 and contacts 2.

A spring 11 is compressed between the end of clamp 6 and a cleat 12 and urges the clamp towards contacts 2. This insures constant and uniform pressure of the working faces of brushes 7 against the contact surfaces. The above-mentioned arrangement of axles 9 and 10 and of brushes 7 insures substantially complete coincidence of the plane of action of the force causing displacement of brushes 7, when yoke 4 is turning, with that of the friction force resisting this displacement.

Thus, in the switch of the present invention there arises but a negligible tilting moment which would cause irregular distribution of pressure on the contact surface.

What is claimed is: I

1. A multicontact switch comprising abase, make-andbreak contacts mounted separately on said base, a yoke supported for displacement relative to said base and said contacts thereon, current-carrying brushes attached to said yoke for making contact with said contacts, said brushes and contacts having opposed surfaces and means attaching said brushes to said yoke for rotation about intersecting axes disposed in a plane substantially coinciding with the opposed surfaces of the brushes and said contacts, said means comprising a pair of intersecting axles respectively extending along said axes in said plane and supporting said brushes for pivotal movement about said axes.

2. A switch as claimed in claim 1, wherein said means further comprises a clamp supporting said axles and mounted freely in said yoke and urged towards said contacts for urging the brush surfaces against the contact surfaces.

3. A switch as claimed in claim 2 comprising spring means acting on said clamp and yoke to urge the clamp resiliently towards said contacts.

4. A switch as claimed in claim 3, wherein said yoke is supported for rotation relative to said base.

5. A switch as claimed in claim 4, wherein one of said axles extends in the direction of displacement of said yoke and the other axle extends perpendicular to said direction of displacement.

6. A switch as claimed in claim 2 comprising means connecting said brushes to said other axle for rotation thereabout, said one axle being pivotably connected to said clamp.

References Cited UNITED STATES PATENTS 2,097,019 10/ 1937 Clough. 2,186,165 1/ 1940 Clough. 2,430,215 11/ 1947 Doucette. 2,877,314 3/ 1959 Great. 3,135,840 6/ 1964 Ausfeld 200-8 ROBERT K. SCHAEFER, Primary Examiner I. R. SCOTT Assistant Examiner US. Cl. X.R. 200-166 

